Metal-treating composition



Patented Sept. 8, 19.25.

- UNITED STATES PATENT OFFICE.

FBEDEIR'IGK M. BECKE'I', OF NEW YORK, N. Y., ASSIGNOR TO ELEC'IRO METALURGICAL COMPANY, OF NEW YORK, N. Y., A CORPORATION OF WEST VIRGINIA.

METAL-Y'IREATING COMPOSITION.

No Drawing.

To all whom it may concern:

Be' it known that I, FREDERICK M. BECKET, a citizen of the United States of America, residing at 565 Park Avenue, New York, in the county of New York and State of New York, have invented certain new and.

useful Improvements in Metal-Treating Compositions, of which the following is a specification.

In a patent issued to me on August 15, 1922, No. 1,425,572, I have disclosed andclaimed certain novel alloys comprising silicon and'fzirconium, usually in association 7 with iron, the silicon being in suflicientamount to prevent the formation of zirconium carbide -in proportions to interfere materially either with the preparation of the alloy or with its solution in molten steel.

In said patent I have also disclosed and claimed a rocess whereby such alloys may be prepare in the electric furnace by direct reduction of a charge comprising silica, a,

- zirconium ore, a carbonaceous reducing agent .and a source of iron.

My further researches have shown that the value of alloys. of the zirconium-silicon type isconsiderably enhanced by the presence therein of. manganese, with or without certain other elements as mentioned below.

The manganese may substitute a part or allof the iron in alloys of the ferrosiliconzirconium type. As in the patent men tioned above, the proportion of silicon v should be sufficient to prevent the formation 86 of'zirconium carbide in interfering quantities when the alloy is prepared by direct carbon reduction in the electric furnace. When the alloy (or the aggregate mentioned below) is prepared by other methods as deportions which do not readily yield a hon 1ogeneous 'alloy. In 'such cases:I pre area mixture of the silicon, zirconium an manganese, or of their allo combinations with each other or with other metals suchas of clean steel.

Application iiled May 22, 1922. Serial No. 562,824.

iron, aggregating or bonding such mixture by means of a metal or material which will not interfere with the intended application of the product. As such binding'or aggregating medium I prefer to use lead, partlcularly where'the mixture is to be used for the treatment of steels. I may however use other metallic or non-metallic binders, in-

eluding fluxes, such as borates, boric acid, I

fusible slags or the like. The preparation of such aggregates is more fully disclosed in m 44? led September 3, 1921.

The present invention relates therefore in its preferred embodiment to a novel composition, alloy or aggregate containing as its essential components silicon, zirconium and manganese; and to the treatment of molten steel with the same. Iron is usually rescnti but is not an essential in e ient.

Other metals or elements, or non-metallicadditions, may. be present in any desired proportion; and as hereinafter pointed out the manganese may be partly or wholly substituted by certain other elements, and notably by calcium or boron, which possess in common with mang'anesethe capability of lowering the meltlng point of silicazirconia slags.

I have discovered that the presence of manganese enhances to a considerable degree the deoxidizing and scavenging action of the other two essential components above mentioned, and particularly that of zirco-.

nium. I ascribe this observed effect more especially to the powerful fluxing action of the basic manganese oxide, formed as a result of the usual oxidation reactions, upon the oxides of silicon and zirconium concurrently produced. Themanganese, which is present as an alloyed or incorporated cons stituent, is capable when oxidlzed of pro pending application Serial No. 498,- v

moting to a maximum degree the formation I of a fusible slag and hence the production This increase in fusibility corresponds, in other words, to the effect of this basic oxide in lowering the melting point of a silica-zircom'a slag. Similar e fects in varying de ee are obtainable by means of the oxidatlon-products of certain other elements, and particularly ca cium and boron: it iswithin my invention herefore to. substitute the manganese in this composition either wholly or partly by such other elements. Or as noted above, boric oxid may be otherwise introduced into the composition as a bonding material or a component thereof.

I have also found that by no means the least advantage which the alloy or aggregate of zirconium, silicon and manganese possesses in comparison with a similar composition of matter without manganese lies in the higher recovery of zirconium obtained in the finished steel in the case of the former. My experiments indicate, for instance, that the percentage of recovery of zirconium in the steel when a zirconium-silicon-manganese combination is used may be at least 10 per cent higher than when combinations of zirconium, silicon and iron are used under otherwise similar conditions.

My preferred method is to produce the zirconium-silicon-maganese composition directly as an alloy by carbon reduction in the electric furnace by means of the procedure described in the patent above mentioned, the charge being appropriately modified.

However, my present invention is not restricted to a composition of matter made in this particular manner. I have, for instance, obtained the desired result by simple fusion of ferromanganese in the desired proportions with an alloy containing zirconium, silicon and iron. Another method of obtaining the same result is by briquetting or aggregating mixtures of ferrosilicon-zirconium and ferromanganese, using lead or other fusible metal, alloy, flux or substance not objectionable in the composition as a bond; or by stirring ferrosilicon-zirconium and ferromanganese, or a mixture of the two, into a bath of molten lead or other appropriate material and allowing the resultant mass to solidify. I

Theuse of lead as an agglomerating or aggregating medium makes possible the production of certain zirconium-silicon-manganese compositions which it is either difficult or impossible to obtain by means of simple fusion, or by direct reduction methods without the introduction of deleterious percentages of carbon. V

The relative proportions of zirconium, silicon and manganese in the alloy or aggregate is determined by the desired composition of the finished steel, and particularly by the percentage of zirconium which it is desired to introduce into the steel bath. Since any or all of the three essential elements of the alloy or aggregate are fregluentlyrequired to be added not only as eoxi izing and scavenging elements, but also as alloying elements, it is at once evident that the preferred relative proportions cannot be arbitrarily limited to any particular range of composition.

I have for instance, made use of an alloy prepared by carbon reduction in the electric furnace and analyzing as follows:

Per cent. Zirconium 13.73 Silicon 51.72 lWanganese 29.08 Carbon 0.05

The balance principally iron.

Using metallic lead as a bond, have produced and made use of an aggregate analyzing as follows:

Per cent.

Zirconium 18.92 Manganese 25.20 Silicon 25.91 Lead L 12. 33

The balance principally iron.

By melting ferromanganese with an alloy of silicon, iron and zirconium, I have produced such alloys as the following:

Per cent. Per cent.

Zirconium 6. 41 12. 30 Silicon 50. 547 28. 92 Manganese 20.05 28. 36 Iron 22. 34 29. 37

, ganese of such an analysis as to introduce the necessary amounts of these three elements by a single addition of the abovedescribed alley or aggregate for any given grade of steel.

In the treatment of steel I prefer to introduce my novel product as a ladle addition, although under exceptional conditions it may be added in the furnace.

The amount of manganese which the alloy or aggregate contains largely influences the cost of manufacture, especially when present above a certain amount. From practical considerations I prefer usually to limit the managanese content to 50% or under.

Where it is desired for any sufiicient reason to use a zirconium-silicon-manganese alloy or aggregate for the purpose of introducing in one addition the amounts of these threeelements which are desired in the manufacture of ordinary carbon or alloy steels, I have found it advantageous in many instances to employ compositions analyzing as follows N0. 1. N o. 2.

Per' cent. Per cent.

Manganese n 50. "40 Silicon 25. 2O Zirconium 3.5 20

The balance principally iron.

While I have emphasized in the foregoing the advantages possessed by my composition containing manganese as compared with similar compositions containing zirconium and silicon but without manganese, I wish to point out that; when the silicon content of my novel product is comparatively low, it is possible to regard it essentially as an improved modification of ferrozirconium, in

which the iron content of the latter is larsgely characteristic of zirconium-treated steels,

whether the addition is in the form of an alloy or of an aggregate containing lead or other fusible binder; and that these desirable characteristics are obtainable with a lminimum percentage of added zirconium, of this metal in the finished steel. The use of thesealloys or compositions is not limited to the treatment of steel, as they are also applicable to the treatment of molten metallic baths in general, including for example cast iron, bronzes, copper, and other non-ferrous metals and alloys.

Claims: 7

1. A composition suitable for treating molten metal and comprising as its essential components, zirconium, silicon, and an effective quantity of a non-ferrous component capable of lowering the zirconia-silica slags, said composition containing zirconium not combined with carand having a silicon percentage in ex cess of half the zirconium percentage. Y 2. A composition suitable for treating molten metal and comprising as its essential components, zirconium, silicon, and anefi'ective quantity of manganese; said composition containing zirconium not combined with carbon, and having a silicon percentage in excess of half the zirconium percentage.

3. An alloy compriiing as its essential reason of the relatively high recoveries melting point of components, zirconium, silicon, and an effective quantity of manganese, said composition containing zirconium not combined with carbon, and having a silicon percentage in excess of half the zirconium percentage.

4. A composition suitable for treating molten metal and comprising as its essential components, zirconium, silicon and man ganese, therefor.

5. A composition suitable for treating and a fusible bonding material .molten metal and comprising as its essential components, zirconium, silicon and manganese, .and a fusible bonding material therefor, -said bonding material comprising lead. a

6. Process of treating molten metal comprising introducing thereinto a composition comprising zirconium, silicon, and an effective quantity of manganese, said composition containing zirconium not combined with carbon, and having a silicon percentage in excess of half the zirconium percentage.

7 Processof treating molten metal comprising introducing ther'einto a composition comprising zirconium, s1l1con, manganese and lead.

prising introducing thereinto a composition comprising zirconium, silicon, and an efiective quantity of a n0n-ferrous component capable of lowering the melting point of zirconia-silica slags, said composition con- 8. Process of treating molten metal comtainmg zirconium not combined with car.

bon', and having a silicon percentage in excess of half the zirconium percentage.

9. Process of treating molten metal comprising introducing thereinto a composition tive quantity of a non-ferrous element yielding oxidation products capable of lowering the melting point of zirconia-silica slags,

comprisin zirconium, silicon, and an eflecsaid composition containing zirconium not combined with carbon, and having a silicon percentage .in excess of half the zirconium percentage.

In testimon whereof, I afiix my signature.

FREDERICK M. BECKET. 

